Mosquitoes are a problem, especially when they carry viruses like dengue and Zika that they can pass on to unsuspecting people with a bite. Since there is no vaccine against dengue, public health experts must focus on controlling the blood-sucking critters themselves. As cities grew large, mosquitoes, in search of stagnant water, moved to the sewers to reproduce, making them harder to control. In response to this problem, a team of scientists from the Taiwan National Mosquito-Borne Diseases Control Research Center had an idea: send robots.
It’s a method that has been tested in other countries, but often with flying robots monitoring the ground below, not remote-controlled caterpillars sniffing sewers. In a new study published this week in PLOS neglected tropical diseases, the team sent unmanned vehicles underground to examine and eliminate mosquito larvae that have collected in ditches under and around the city of Kaohsiung in southern Taiwan. After all, it is much easier to get the pests before they grow wings than to catch them in the air.
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These multifunctional robots come with a range of tools, digital cameras and LED lights that allow them to visualize the sewage environment, detect mosquito larvae in areas of stagnant water, and spray the area with insecticide or blast it with hot water. The wheeled robots crawl at a speed of 5 meters/min (that’s 16 feet per minute). They are also designed so that they cannot be knocked over in areas where it would be difficult for people to put them back on their feet. The target for these robots are mosquitoes in the genus Aedescontaining several species that commonly carry contagious tropical diseases.
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To monitor mosquito activity around the trenches, scientists have also set up a series of Gravitraps that can be used to lure and trap female mosquitoes. The team later analyzed these specimens to see where the dengue-positive mosquitoes go. In many ditches where there were high concentrations of dengue-positive mosquitoes, traps following deployment of the robots showed that dengue positivity rates dropped (probably because the mosquito population as a whole also took a dip), indicating that the bots could be a useful tool for disease control and prevention. Of course they can always be improved. With better sensors, AI, mobility and autonomy features, these robots can become more usable and practical.
